Method and apparatus for processing three-dimensional structure, method for producing three-dimensional shape product and three-dimensional structure

Abstract

Disclosed is a method for processing a three-dimensional structure having a fine three-dimensional shape and a smooth surface is disclosed in which the three-dimensional structure is usable for an optical device.The process method comprises the steps of depositing a thin layer for absorption of laser light on a flat substrate; depositing a transparent layer on the thin layer for absorption of laser light; and irradiating a process laser light, passing through the transparent layer; in which pulse injection energy of the process laser light is set to be the same as or smaller than the maximum pulse injection energy capable of exposing a surface of the thin layer in front in the incident direction of the process laser light, and to be set the same as or greater than the minimum pulse injection energy capable of removing the transparent layer in rear in the incident direction of the process laser light.

What is claimed is:  
     
       1. A method for processing a three-dimensional structure, comprising the steps of: 
       depositing a thin layer for absorption of laser light on a flat substrate;  
       depositing a transparent layer on said thin layer for absorption of laser light; and  
       radiating a process laser light, passing through said transparent layer to said thin layer and absorbing it in said thin layer;  
       wherein pulse injection energy of said process laser light is set to be the same as or smaller than the maximum pulse injection energy capable of exposing a flat surface of said thin layer for absorption of laser light at an interface between said thin and said transparent layers, and set to be the same as or greater than the minimum pulse injection energy capable of removing said transparent layer.  
     
     
       2. A method for processing a three-dimensional structure as claimed in  claim 1 , wherein said thin layer for absorption of laser light has a thermal diffusion rate greater than said flat substrate. 
     
     
       3. A method for processing a three-dimensional structure as claimed in  claim 1 , wherein a portion of said transparent layer, said process laser light passing through said portion, and a portion of said thin layer for absorption of laser light, said process laser light penetrating into said portion, are together removed by one-shot pulse radiation of said process laser light. 
     
     
       4. A method for processing a three-dimensional structure as claimed in  claim 1  or  3 , wherein a thermal insulation layer having a smaller thermal diffusion rate than said flat substrate is deposited on said flat substrate, and then said thin layer for absorption of laser light is deposited onto said thermal insulation layer. 
     
     
       5. A method for processing a three-dimensional structure as claimed in  claim 3 , wherein said thin layer for absorption of laser light and said transparent layer are further alternately laminated in a plurality of pairs, and a one-shot laser pulse of the process laser light removes the pair of said thin layer for absorption of laser light and said transparent layer, whereby a removed material section having different depths is formed by removing pairs of the layers in accordance with the number of the one-shot laser pulses. 
     
     
       6. A method for processing a three-dimensional structure as claimed in one of  claims 1  to  3  or  5 , wherein said process laser light is a fundamental or a harmonic of light emitted from excimer laser or a solid laser and has a pulse width less than 100 ns. 
     
     
       7. A method for processing a three-dimensional structure as claimed in  claim 3 , wherein thickness of said transparent layers is different from each other. 
     
     
       8. A method for processing a three-dimensional structure as claimed in  claim 1  or  2 , wherein the radiation of said process laser light is carried out by transferring a mask pattern thereto. 
     
     
       9. A method for processing a three-dimensional structure as claimed in one of  claims 1  to  3 ,  5  or  7 , wherein the process is carried out by shifting the position of a laminate comprising said flat substrate, said thin layer for absorption of laser light and said transparent layer relative to the radiation position of said process laser light. 
     
     
       10. A method for processing a three-dimensional structure as claimed in  claim 3 , wherein said process laser light is focused in the form of a round shape to impinge on said thin layer for absorption of laser light. 
     
     
       11. A method for processing a three-dimensional structure as claimed in  claim 3 , wherein said process laser light is focused in the form of a straight line to impinge on said thin layer for absorption of laser light. 
     
     
       12. A method for producing a three-dimensional shape product, wherein a duplicate is formed from a three-dimensional structure produced by the method for processing a three-dimensional structure as claimed in  claim 1 , and then a three-dimensional shape product having the same shape as the duplicate or an inversed shape with respect to said duplicate is formed. 
     
     
       13. A method for producing a three-dimensional shape product, wherein the duplicate as claimed in  claim 12  is used as a stamper for a light-recording medium. 
     
     
       14. A method for producing a three-dimensional shape product, wherein the duplicate as claimed in  claim 12  is used as a metal mold for a diffraction optical element. 
     
     
       15. A method for processing a three-dimensional structure as claimed in  claim 2 , wherein a portion of said transparent layer, said process laser light passing through said portion, and a portion of said thin layer for absorption of laser light, said process laser light penetrating into said portion, are together removed by one-shot pulse radiation of said process laser light. 
     
     
       16. A method for processing a three-dimensional structure as claimed in  claim 4 , wherein said process laser light is a fundamental or a harmonic of light emitted from excimer laser or a solid laser and has a pulse width less than 100 ns. 
     
     
       17. A method for processing a three-dimensional structure as claimed in  claim 4 , wherein the process is carried out by shifting the position of a laminate comprising said flat substrate, said thin layer for absorption of laser light and said transparent layer relative to the radiation position of said process laser light. 
     
     
       18. A method for processing a three-dimensional structure as claimed in  claim 6 , wherein the process is carried out by shifting the position of a laminate comprising said flat substrate, said thin layer for absorption of laser light and said transparent layer relative to the radiation position of said process laser light. 
     
     
       19. A method for processing a three-dimensional structure as claimed in  claim 8 , wherein the process is carried out by shifting the position of a laminate comprising said flat substrate, said thin layer for absorption of laser light and said transparent layer relative to the radiation position of said process laser light. 
     
     
       20. A method for producing a three-dimensional shape product, wherein a duplicate is formed from a three-dimensional structure produced by the method for processing a three-dimensional structure as claimed in one of claims  2 ,  3 ,  5 ,  7 ,  10  or  11 , and then a three-dimensional shape product having the same shape as the duplicate or an inversed shape with respect to said duplicate is formed. 
     
     
       21. A method for producing a three-dimensional shape product, wherein a duplicate is formed from a three-dimensional structure produced by the method for processing a three-dimensional structure as claimed in  claim 4 , and then a three-dimensional shape product having the same shape as the duplicate or an inversed shape with respect to said duplicate is formed. 
     
     
       22. A method for producing a three-dimensional shape product, wherein a duplicate is formed from a three-dimensional structure produced by the method for processing a three-dimensional structure as claimed in  claim 6 , and then a three-dimensional shape product having the same shape as the duplicate or an inversed shape with respect to said duplicate is formed. 
     
     
       23. A method for producing a three-dimensional shape product, wherein a duplicate is formed from a three-dimensional structure produced by the method for processing a three-dimensional structure as claimed in  claim 8 , and then a three-dimensional shape product having the same shape as the duplicate or an inversed shape with respect to said duplicate is formed. 
     
     
       24. A method for producing a three-dimensional shape product, wherein a duplicate is formed from a three-dimensional structure produced by the method for processing a three-dimensional structure as claimed in  claim 9 , and then a three-dimensional shape product having the same shape as the duplicate or an inversed shape with respect to said duplicate is formed.